Add -M option to test.py

specify-modules.patch

diff --git a/test.py b/test.py
--- a/test.py
+++ b/test.py
@@ -1122,7 +1122,14 @@
             example_names_original,
             python_tests)
 
-    for module in NS3_ENABLED_MODULES:
+    # User can specify which modules to test
+    if options.modules == "*":
+        enabled_modules = NS3_ENABLED_MODULES[:]
+    else:
+        specified_modules = options.modules.split(",")
+        enabled_modules = ["ns3-" + module_name for module_name in specified_modules]
+
+    for module in enabled_modules:
         # Remove the "ns3-" from the module name.
         module = module[len("ns3-"):]
 
@@ -1882,6 +1889,10 @@
     parser.add_option("-m", "--multiple", action="store_true", dest="multiple", default=False,
                       help="report multiple failures from test suites and test cases")
 
+    parser.add_option("-M", "--modules", action="store", type="string", dest="modules", default="*",
+                      metavar="MODULES",
+                      help="comma separated list of modules from which test suites will be used")
+
     parser.add_option("-n", "--nowaf", action="store_true", dest="nowaf", default=False,
                       help="do not run waf before starting testing")